ZURICH (Reuters) - The U.S. Food and Drug Administration has rejected Novartis’s bid to repurpose a drug now approved for rare inflammatory diseases to be used in a group of heart attack survivors, the Swiss drugmaker said on Thursday.

FILE PHOTO: Swiss drugmaker Novartis' logo is seen at the company's plant in the northern Swiss town of Stein, Switzerland October 23, 2017. REUTERS/Arnd Wiegmann/File Photo

The company received an FDA letter turning down its bid to make canakinumab a targeted therapy for those cardiovascular patients who in tests had quickly responded to treatment, as levels of a protein in their blood associated with inflammation and heart disease quickly plunged.

Canakinumab made headlines in 2017, when data from a six-year study of about 10,000 patients proved that fighting inflammation with the drug - not merely lowering cholesterol - helped heart attack victims avoid future attacks or death.

But while scientists lauded the results of Novartis’s Cantos study as a revelation, the benefit of the medicine was downplayed by some cardiovascular experts who concluded it was insufficient to justify expanding existing approvals to routine use in cardiac patients.

“Based on the correspondence, the Cantos data would not support labeling for the use of canakinumab as a targeted therapy for those patients with cardiovascular disease who achieved a reduction of hsCRP below the 2 mg/L target,” Novartis said in a statement.

A big challenge Novartis always faced with canakinumab, also known as Ilaris, is it now costs some $200,000 annually for treating rare inflammatory diseases like Mediterranean fever.

Cardiology drugs costs just a fraction of that, so Novartis would have had to win favorable labeling from regulators.

“We’re now evaluating the full details of what’s in the complete response letter, and trying to determine what is the best course of action,” a Novartis spokesman told Reuters. “It’s not clear what the next steps are.”

The cardio market is huge, with a quarter of the 1.3 million people who suffer heart attacks in the United States and Europe annually likely to have another attack within five years.

But in its current uses, Ilaris is comparatively small, racking up sales of $402 million last year.

In trials for heart disease, Novartis discovered a potential benefit in lung cancer patients for the drug, prompting the company to start cancer trials and to promote the medicine’s potential for smokers who also suffered from heart disease.

In spite of the FDA snub in heart disease, Novartis said Phase 3 canakinumab trials in non-small cell lung cancer would continue and are due to be completed in 2022.